Lobster Cooking Times by Weight: Complete Temperature Guide (2026)

You came for a number, so here it is below: every size from a one-pound chick to a ten-pound jumbo, boiled or steamed, timed from the second the water climbs back to a boil. Bookmark it and skip the rest.

Weight sets the time, and almost nothing else does. A lobster’s own weight, off the scale or the label, not the combined weight of the pot and not whatever recipe you are chasing. Find your row, pull at 135 to 140°F, done. The stuff under the chart is the short list of things that nudge the number a minute or two, and most nights none of them apply to you. For the full method, boiling through grilling, that all lives in our complete lobster cooking guide.

Why Cooking Times Vary So Much Online

Search “how long to cook lobster,” and you get a dozen answers: 7 to 10 minutes a pound here, a flat 6 to 9 minutes there, an old 4 to 5 minutes somewhere else. No wonder people overcook it.

The problem is the “minutes per pound” rule itself. Lobster does not cook in a straight line. As it gets heavier, its mass grows faster than its surface area, so a 3 lb lobster does not need three times as much time as a 1 lb lobster. Multiply a per-pound rule out, and you land on 21 minutes for a 3-pounder when it really wants 12 to 14. That one mistake is behind most tough, rubbery lobsters.

The chart below is the one we cook by, built on each lobster’s own weight and a 135 to 140°F finish. Use it as your starting point, then let the thermometer make the final call. It is the only number that never lies.

How Long Do You Cook Lobster by Weight?

Steam for a whole-lobster dinner, boil when you are picking meat for rolls or a crowd. Both finish at 135 to 140°F in the tail. Time each lobster by its own weight, not the combined weight of the pot, and start the clock when the water returns to a full boil, not when the lobsters go in.

Cooking Times by Weight

Weight	Boil	Steam
1 lb	6–7 min	7–8 min
1¼ lb	7–8 min	8–9 min
1½ lb	8–9 min	9–11 min
2 lb	10–12 min	11–12 min
2½ lb	11–13 min	12–13 min
3 lb	12–14 min	12–14 min
4 lb	15–17 min	17–20 min
5 lb	18–20 min	22–24 min
6 lb	20–23 min	24–27 min
7–8 lb	23–28 min	27–32 min
9–10 lb	30–34 min	34–38 min

Pull Temperature: 135–140°F in the tail. FDA guidance is 145°F.

Salt: ¼ cup salt per gallon.

Water: 1 gal per lobster for boiling; 2 inches for steaming.

Crowding: If boil stops for >30 sec, run batches.

Boil

Steam

Doneness

Pot sizes

Large lobsters

High altitude

Food-safety reference: FDA seafood temperature and doneness guidance.

Four 1½ pounders are four nine-minute lobsters, not one thirty-six-minute lobster. Timing a batch by its total weight is the single mistake that ruins more lobster than everything else combined.

Why a Minute Matters So Much

Fish has short muscle fibers that flake apart the moment they cook, which is why fish forgives you. Lobster is the opposite: long, dense fibers packed in tight, and they go from set to seized in a narrow window. Hold them in the sweet spot and the meat stays sweet and firm. Push past it and the proteins clench, wring out their own moisture, and hand you rubber. That is the whole reason two extra minutes wrecks a lobster when the same two minutes barely touches a fillet of cod.

Lobster Cooking Time Adjustments: Shell Type, Altitude & More

Shell beats the calendar. A hard shell wants a minute or two past the chart. A soft shell overcooks in a blink, so cut a minute and stand there watching it. A lot of the Maine catch from July into late September comes in soft, but every lobster is graded before it ships, which is how we send hard and firm shell in the dead of January. If your box came from us, run the full time. If you grabbed one off a dock in August, squeeze the side of the body first: a soft shell gives, a hard shell does not. Hard shell vs soft shell

Altitude. The higher you are, the cooler water boils, roughly 1°F for every 500 feet, so the same pot cooks slower. Add about two minutes, keep the lid down tight, and let the thermometer have the last word. High-altitude lobster cooking

Frozen and thawed. Thaw it all the way in the fridge first, 12 to 24 hours, then cook it on the fresh-lobster times. Still icy in the middle? Give it an extra minute. Do not drop it in frozen, or the outside turns to rubber waiting for the middle to catch up. Storing and thawing

Pull it at 135 to 140°F in the thickest part of the tail, going in from the side nearest the body. When the timer and your eyes disagree, this is the tiebreaker. FDA guidance for seafood is 145°F, and a lobster you pull at 135°F drifts up to 140 to 145°F just sitting on the counter. One thing the color will not tell you: red only proves that heat happened, not that the inside is cooked. Doneness, temperature, and visual cues

Other Methods and Tails

These times are for whole lobster, boiled or steamed. Grilling, baking, broiling, and the rest run on their own clocks, and lobster tails run differently again. Pick a method from the complete cooking guide, or jump straight to cooking lobster tails.

Past 5 Pounds

The old line is that big lobsters cook up tough. They do not. What is true is that they are easy to overshoot, because the times printed for them run long and a jumbo has enough thermal mass to hide the truth from you until you cut it open. Bring the pot up, put the lobster in, then back the heat off so it poaches instead of rolling hard. Low and slow buys you margin on a big one, the same as it does on a roast. Large lobster times and technique

If It Came Out Wrong

Rubbery all the way through means it cooked too long, and honestly that is the only thing that does it. Some pieces done and others still glassy means the pot was crowded or you ran mixed sizes in one batch. Meat that comes out mushy or cottony was never a timing problem at all: that lobster went in weak or already gone, and no clock in the world fixes sourcing.

Melt the butter while you wait, since that is honestly the only job you have for the next nine minutes. Then put the meat to work: lobster rolls · salad · pasta · thermidor. For the full method walk-throughs, start at the complete lobster cooking guide.

Lobster Cooking Time FAQ